The disclosures herein relate generally to compressors and more particularly to roller devices for assisting in the insertion and removal of a compressor bundle relative to a compressor casing.
The insertion of the centrifugal flow compressor bundle into the compressor casing, and the removal of the bundle from the casing is a difficult task due to the massive size and weight of these devices. For example, the compressor bundle may vary in weight from about 5,000 pounds to about 70,000 pounds. The bundle is an annular member which inserts into an annular cavity formed in the casing. There is a close tolerance between the outer annular surface of the bundle and the mating inner annular surface of the cavity. In addition, the mating annular surfaces of these devices are stepped, i.e. they have stepped diameter portions. Thus, the task of inserting the bundle into the casing and removing the bundle from the casing, is difficult to achieve with the precision needed to accomplish the task and avoid damage to the mating members.
The assembly difficulty is greatest when the step is large between the non pressurized portion of the case and the pressure containing section. Normal lifting, by slings and hoists cannot be accomplished due to the center of gravity of the bundle being inside the case before the bundle can be inserted into the pressure containing portion of the case. Since the normal methods of insertion cannot provide a support on both sides of the center of gravity, the bundle will tip and not be able to be inserted into the stepped section. There is no known support system built into the non-pressure containing portion of the case to provide the support and guidance of the stepped bundle to mate with the stepped portion of the case.
In U.S. Pat. No. 4,925,363, a roller bearing is located at one end of a support shaft and a flange is located at the other end along with insertable shims of different thicknesses which can be used to adjust the length of the support shaft. This arrangement provides support to the inner casing of a turbine or compressor during assembly or disassembly, and permits removal of the casing without removal of the turbine or compressor rotator. The inner casing can be rolled around the turbine circumference with the aid of large chain hoists.
In U.S. Pat. No. 3,493,212, a roller bearing is at one end of a support shaft and a flange at the other end, but uses jackscrews instead of insertable shims to allow the adjustment of its length.
In U.S. Pat. No. 5,326,222, the shaft of a turbine is supported while it is running, and is connected to the turbine shaft bearing casing by means of a pin joint. The device is adjustable and is built into the casing of the turbine but is not assist in the assembly or disassembly of the turbine.
Therefore, what is needed is a system for supporting a centrifugal flow compressor bundle during its removal from and insertion into the compressor casing, which is capable of supporting the massive compressor bundle for precise movement relative to the casing.